oh and also, its of my opinion that you will pop that 1310 or 1350 u-joint long before you pop the axle. another 2 cents, so thats 4

99.9% of the time, the breaking of the joint destroys the yoke, thus requiring the replacement of the axle shaft. just sayin.

2010 Magnetic Toyota 4Runner Trail Teams

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man im so glad this thread actually had valuable info, normally when i click on any thread regarding a 37" tire its normally 50 comments saying "search" or "you dont need 37s". so thank you guys for actually talking about it!

ive been trying to decide what to do to run 37's on an LJ. with a d30 front and d44 rear would upgraded to a tj rubi d44 front be good? or would i need to throw a 8.8 in the rear? my other option is jk rubi axles. $3000 shipped is the cost for the JK axles though and the mounting brackets i have seen range from $500-$1000.

so with that said what axle setup would you guys do? i wont be doing any rock crawling just some medium trails at uwharrie and just some other easy stuff.

If you're going to be wheeling exclusively at Uwharrie you will get bored really fast on 37s. If that is your sole stomping grounds, save yourself some money and stay on 33s.

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Myself and 5 others in our group are all running 37's on our LJ's all are Rubicons. And all but myself are running stock shafts. Mine tossed a u-joint cap and broke the stub shaft and beat the H*** out of the short side yoke at highway speeds. So i up graded to RCV D44 axle shafts.

We have pretty much a mud up to the windows or Rock and a lot of both on every trip. at least 1 a month, and if the stars line up right we get in 2 trips. and there is a ton of taunting to challenge each other to the extreme. with no problems. There are ways to add strength to the axles if needed for your type of wheeling. But i would not worrie about it. Under the right cirumstances anything will break.

man im so glad this thread actually had valuable info, normally when i click on any thread regarding a 37" tire its normally 50 comments saying "search" or "you dont need 37s". so thank you guys for actually talking about it!

ive been trying to decide what to do to run 37's on an LJ. with a d30 front and d44 rear would upgraded to a tj rubi d44 front be good?

Nope, a D30 is not up to 37" tires and it can't be made suitable for 37" tires, not even with a Super 30 kit. Besides, even the rear Dana 44 is not really up to 37" tires either. Those axles should really be limited to 35" and even then with caveats.

Gone wheeling, back Sunday evening.

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I am late to this thread, but have been running 37" MTR's on the stock TJ Rubicon D44 front and rear, with Superior chrome moly shafts with no issues so far. The degree of abuse includes Pritchett Canyon, Behind the Rocks, Rubicon Trail. Nothing's broken so far, not to say it never will, but so far perfect and axle tubes haven't bent. I'm using 4:88 gears right now, somebody told me if I go higher than 4:88 the pinion gear gets too weak? Anybody know anything about that?

Conventional wisdom seems to be to limit the D44's to 35" tires, and I am not here to disagree. I guess I'll be the guinea pig, I'll be sure to post up if I break anything. I have no shame. So far I have just the one season on the 37's.

So far my D44 on the said Rubicon with stock axles are doing fine with 35's. However, I do not trash on my rig. The last upgrade I did was front and rear truss and will upgrade axles soon with a PSC kit. Then I will probably go 37's and see what happens. I feel good about the axles and like loaderopp said "Under the right cirumstances anything will break"

I'd run sticky 35s before I'd run 37s again. No issues when I ran them though.

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I am late to this thread, but have been running 37" MTR's on the stock TJ Rubicon D44 front and rear, with Superior chrome moly shafts with no issues so far. The degree of abuse includes Pritchett Canyon, Behind the Rocks, Rubicon Trail. Nothing's broken so far, not to say it never will, but so far perfect and axle tubes haven't bent. I'm using 4:88 gears right now, somebody told me if I go higher than 4:88 the pinion gear gets too weak? Anybody know anything about that?

Conventional wisdom seems to be to limit the D44's to 35" tires, and I am not here to disagree. I guess I'll be the guinea pig, I'll be sure to post up if I break anything. I have no shame. So far I have just the one season on the 37's.

To put one aspect of your trail usage in some sort of perspective, if you consider the average trail than can be run day in and day out on 35's in JV on a 10 scale as being a 10, the Rubicon would rate about a 4 or 5 if you avoid Little Sluice.

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My opinion, if you over build a Rubi 44 axle, you can wheel them on 37"s. But keep in mind, you are absolutely maxing out that axle. This leaves very little room to be aggressive with them, which at the end of the day, will limit what you can do on the trail.

I have been running some of the heaviest 37"s you can buy on built Rubi 44 axles over the past 2 1/2 years and here is what I have experienced- In about 45 trail runs and 1 off-road endurance race on 37" Pitbull Rockers and Rubi 44's, I have broken:

One set of Alloy USA 4.88 ring and pinion

Two lower control arm mounts

One upper control arm mount

ARB copper air line (probably not the fault of the tires)

Rear shock mount

Two broken stock axle shafts

Three broken wheel studs

Two bent rear Alloy USA axle shafts

Two Timkin hubs

Mine are about as built as I could get them:

Front Rubi 44:

Nitro Super 44 Kit (30 spline shafts)

Alloy USA 4.88s

ARB

Gusseted outer C's

Genright control arm mounts

Currie HD steering system

Vanco big brake kit

Rear Rubi 44:

Alloy USA 30 spline shafts

Alloy USA 4.88s

ARB

Clayton 4 link truss

I would love to have some Spider 9's, but until I can afford some true race axles, I will continue to use these. But I go into the rocks knowing that I can't sit there on the gas spinning, sliding, and bouncing. They are not perfect, but built up, would work for most wheelers I would assume.

Nope, a D30 is not up to 37" tires and it can't be made suitable for 37" tires, not even with a Super 30 kit. Besides, even the rear Dana 44 is not really up to 37" tires either. Those axles should really be limited to 35" and even then with caveats.

sorry i didnt really make myself clear, i was asking if a rubi d44 front and a stock d44 rear would be substantial enough. looks like others have said the rubi axles can deal with 37s if you wheel it right and im no hardcore offroader. im still contemplating on the jk d44's though